Device for the mist lubrication of dies for sintering

ABSTRACT

A device for lubricating the walls of a mould cavity of press dies, comprising a lubricating element mounted on an end of an arm, which is traversed along a helical path by a sleeve provided with a helical slot. Consequently the lubricating element is traversed along a continuous path from a parking position to a working position.

United States Patent 1 Ferlito Dec. 31, 1974 DEVICE F OR THE MIST LUBRICATION OF DIES FOR SINTERING [75] Inventor: Guiseppe Ferlito, lvrea, Italy [73] Assignee: Ing. C. Olivetti & C. S.p.A., Ivrea (Torino), Italy 221 Filed: July 16,1973

21 Appl. No; 379,895

[30] Foreign Application Priority Data Aug. 14, 1972 Italy 6 9640/72 Aug. 31, 1972 Italy 69779/72 [52] U.S. Cl lls/300, 118/73, 118/313,

[51] Int. Cl. 1. B05c 7/02 [58] Field of Search 118/72, 73, 300, 313, 315;

[56] References Cited UNITED STATES PATENTS 2,878,063 3/1959 Kish et a1 299/86 3,185,129 5/1965 Sollich 118/315 3,237,598 3/1966 Zahn 118/315 Primary Examiner-Mervin Stein Assistant Examiner-Douglas A. Salser Attorney, Agent, or Firm-1. J. Schaefer 57 ABSTRACT A device for lubricating the walls of a mould cavity of press dies, comprising a lubricating element mounted on an end of an arm, which is traversed along a helical path by a sleeve provided with a helical slot. Consequently the lubricating element is traversed along a continuous path from a parking position to a working position.

5 Claims, 5 Drawing Figures PATENTED DEB3 1 I974.

sum 2 or 5 PATENTEI] DEB31 I974 SHEET 3 [IF 3 DEVICE FOR THE MIST LUBRICATION OF DIES FOR SINTERING CROSS-REFERENCE TO RELATED APPLICATION BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for the mist lubrication of the walls defining the mould cavity of dies for producing blanks for sintering, particularly suitable for application to presses for the compacting of metal powders.

The invention is concerned with avoiding the danger of binding against the walls of the mould cavity of the compacted blank and with facilitating its expulsion from the mould cavity.

A system for lubrication of such dies is known, consisting of the use of suitable solidlubricants, such as zinc stearate, mixed in fixed proportions with the metal powders prior to the compaction. The presence of such lubricating components causes weakness of the compacted blank which can break when it is extracted from the mould cavity. Moreover, such lubricants tend to form zinc oxide deposits on the internal walls and on the other equipment within the sintering furnace, degrading the performance thereof.

Other means for lubricating the dies are also known, consisting of ducts for a lubricating liquid, formed coaxially in the lower punch; such solutions have, however, the disadvantage of weakening the punch and of making its construction more complex.

S'UMMARY or THE INVENTION The object of the present invention is to provide a device for effecting mist lubrication of the inner walls of the mould cavity which obviates the disadvantages explained above,

According to thepresent invention there is provided a device for effecting mist lubrication of the walls of a mould cavity formed by the dies of a press for, forming sintering blanks, comprising means, for creating a mist of lubricant in air, mounted on one end of an arm whose other end is pivoted to a die-carrying plate of the press, and means arranged for simultaneously turning the arm about its pivot and moving the said other end of the arm along the axis of the pivot so as to cause the one end of the arm and the mist creating means to move along a helical arc between a parking position remote from the work zone of the press and an operative position adjacent the mould cavity.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a longitudinal section of a device embodying the invention;

FIG. 2 is a perspective view of the device in which an oscillating arm is in aparking position;

FIG. 3 shows the oscillating arm of FIG. 2 in the operative position; and I FIGS. 4 and 5 show two special shapes of mould cav ity and the corresponding arrangements of the nozzles in an atomizing disc.

DESCRIPTION OF THE PREFERRED v EMBODIMENTS Referring now to the drawings, and more particularly 1 to FIG. 1, a die carrying plate 1 supports a cylindrical housing 2 which hasa lateral window 3 to allow the passage of an oscillating arm 4. The housing 2 is clamped to the plate 1 by means of a hollow cylindrical sleeve 7 passing through the plate and having an externalflange 8 at the top bearing on an internal flange of the housing 2. The sleeve 7 is locked to the plate 1 by means of a nut 9. In the cylindrical wall of the sleeve 7 there is formed a slotted hole 10, following a helical path and in which engages a peg 11 projecting'radially from a cylindrical stem 12 which can move in the sleeve 7. Thetop of the stem 12 widens out into a cup 13 which contains an axial thrust ball bearing 14, the end rings 17 of which are integral with the cup 13, whilst the intermediate ring 18 is connected to a rod 19 integral with a piston (not shown in FIG. 1) of a pneumatic cylinder 20, fixed to a cover 21 of the housing 2.

The oscillating arm 4 is fixed, at its inner end, to the upper surface of the cup 13 and supports at its other, free end, a mixing manifold block 22. A coaxial bore 23 in the block 22 provides for the introduction of the lubricating liquid, supplied through piping 24. A ring of bores 27 around the bore 23 provides for the introduction of compressed air supplied through pipings 28.

On the lower face ofthe block 22, at which there emerge the bores 23 and 27, is fixed a disc 29, in whose top wall there are formed radial channels 30 connecting the central bore 23 to a circular mixing channel 31 lying under the air bores 27. I

A series of atomizing nozzles 32 of small diameter, extending through the disc 29, lead from the circular channel 3 1 to the lower wall of the disc 29. The thickness of the disc substantially exceeds the diameter of the nozzles.

The pneumatic cylinder 20 is moved under thecontrol of devicesof known form and therefore not described herein, the controlbeing synchronised with the work cycle of the compacting press. Also synchronised with the work cycle of the press is the control device for the flow of lubricant and of compressed air, which device is again of known form and therefore not described.

When the lower die punch 33" re-ascends until it moves into the position of FIG. 1, it defines with the die 5 an annular mould cavity 6 for the metal powder to be compacted. The cavity 6 can assume the most varied shapes, according to the shape of the part that is to be compacted; by way of example in FIG. 1 the cavity 6 has an annular shape, whilst in FIGS. 4 and 5 there are shown two other possible shapes.

At this point, compressed air is admitted to the upper chamber of the cylinder 20, the piston of which is thrust downwards. Consequently, the stem 12 slides in the sleeve 7 and the peg ll, guided by the slotted hole 10, causes the stem 12 and the arm 4 to rotate. The free end of the arm and the parts 22 and 29, fixed to it, traverse an arm of helix, starting from a parking position indicated by 25 in FlG. 2, substantially more elevated and backward with regard to the die 5, as far as a position indicated by 26 in FIG. 3, in which the disc 29 moves into a position coaxial with the die and with the cavity 6, at a very small distance from the plane 35 of the die. At this point, through the tubings 24 and 28 there are sent respectively the lubricant and the compressed air which flow down, whilst mixing, in the channels 30 and 31 in order to emerge from the nozzles 32, in the form of a very fine mist in air of particles of lubricant, which laps the inner walls of the cavity 6.

Compressed air is then fed into the lower chamber of the cylinder 20, raising the piston and with it the stem 12 and the arm 4 which moves in reverse through the same are of a helix, and then stops in the parking position 25.

Among modifications within the scope of the invention may be mentioned the following.

For example, the arrangement of the nozzles on the lower face of the disc 29 can vary for the purpose of al lowing an adequate lubrication inside the cavities of dies of more complex shapes.

More specifically (FIG. 4), when the shape of the cavity 6 is such that the distance between opposite walls is greater than the width of the jet of lubricant which emerges from the nozzles 32, the nozzles can be arranged all around the periphery of the chamber. When the cavity 6 assumes, on the contrary, a narrow and elongated shape (FIG. 5), in which the distance between two of its opposite walls is equal to or less than the width of the jet oflubricant which emerges from the nozzles 32, these latter are aligned in a single row along the mean axis 39 of the cavity.

When the arm 4 is in the operative position, shown in FIG. 1, the lower face of the disc 29 is superimposed on the mould cavity 6, at a small distance from the plane 35 of the die 5, so that the nozzles 32 are in correspondence with the side walls of the charging chamber, or with its longitudinal middle line, respectively as in the two cases illustrated previously.

What is claimed is:

l. A device for lubricating the walls of a mould cavity of press dies for forming sintering blanks, said press having a parking remote position and an operative position adjacent the mould cavity comprising:

a die-carrying plate having a coupling element,

means for creating a mist of lubricant in air,

an arm having one end mounting said creating means and another end having a pivot coupled to said coupling element,

means for simultaneously turning the arm about said pivot and for moving said other end of the arm along said coupling element, whereby said creating means are moved along a helical are between said parking position and said operative position.

2. A device according to claim 1, wherein said creating means comprises:

a manifold block rigidly mounted to the said one end,

a plurality of channels included in said block for feeding lubricant and air,

a disc attached to said block,

and a plurality of atomizing nozzles, communicating with said channels and extending through said disc having a thickness substantially greater than the diameter of the nozzles.

3. A device according to claim 2, wherein the nozzles face into the mould cavity in said operative position and are arranged in a row along a line substantially coincident with a peripheral wall of the mould cavity.

4. A device according to claim 3, wherein the nozzles are arranged in a row along a line substantially midway between opposing walls of the mould cavity, said walls closely facing said nozzles to be simultaneously lubricated by the nozzles.

5. A device according to claim 4, wherein said pivot has a pin and said coupling element is provided with a helical slot engaging said pin whereby said arm is simultaneously turned and axially moved as to move said one end of the arm along a helical path.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 857, 363 Dated December 31 1974 Inventor s) Giuseppe Ferlito It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the first page after "Inventor:" delete "Guiseppe" and insert --Giuseppe.

In Claim 1, column 4:

line 5, delete "parking remote" and insert --remote parking--;

line 11, after insert and line 113, delete "other" and insert --another--.

Signed and sealed this 13th day of May 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents "Attesting Officer and Trademarks ORM PC4 uscoMM-Dc 60376-P69 U.S. GOVERNMENT PRINTING OFFICE: I959 0-365-334 

1. A device for lubricating the walls of a mould cavity of press dies for forming sintering blanks, said press having a parking remote position and an operative position adjacent the mould cavity comprising: a die-carrying plate having a coupling element, means for creating a mist of lubricant in air, an arm having one end mounting said creating means and another end having a pivot coupled to said coupling element, means for simultaneously turning the arm about said pivot and for moving said other end of the arm along said coupling element, whereby said creating means are moved along a helical arc between said parking position and said operative position.
 2. A device according to claim 1, wherein said creating means comprises: a manifold block rigidly mounted to the said one end, a plurality of channels included in said block for feeding lubricant and air, a disc attached to said block, and a plurality of atomizing nozzles, communicating with said channels and extending through said disc having a thickness substantially greater than the diameter of the nozzles.
 3. A device according to claim 2, wherein the nozzles face into the mould cavity in said operative position and are arranged in a row along a line substantially coincident with a peripheral wall of the mould cavity.
 4. A device according to claim 3, wherein the nozzles are arranged in a row along a line substantially midway between opposing walls of the mould cavity, said walls closely facing said nozzles to be simultaneously lubricated by the nozzles.
 5. A device according to claim 4, wherein said pivot has a pin and said coupling element is provided with a helical slot engaging said pin whereby said arm is simultaneously turned and axially moved as to move said one end of the arm along a helical path. 